equivocation

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The use of equivocal language.
• noun An equivocal statement or expression.

from The Century Dictionary.

• noun In logic, a fallacy depending upon the double signification of some one word: distinguished from amphibology, which depends upon the doubtful interpretation of a whole sentence.
• noun Ambiguity of speech; specifically, the use, with a view to mislead, of words or expressions susceptible of a double signification; prevarication.
• noun Synonyms Prevarication, etc. (see evasion); shuffling, quibbling, quibble, equivoke.

from the GNU version of the Collaborative International Dictionary of English.

• noun The use of expressions susceptible of a double signification, with a purpose to mislead.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun logic A logical fallacy resulting from the use of multiple meanings of a single expression.
• noun The use of expressions susceptible of a double signification, possibly intentionally and with the aim of misleading.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun intentionally vague or ambiguous
• noun a statement that is not literally false but that cleverly avoids an unpleasant truth
• noun falsification by means of vague or ambiguous language